Piston.



"STATES ATE T when a 1 v mmmm \ man or nnnvnn, mmm, nssron'on 'ro KINCHEN n. Marrnnws, or V T all who-m may concern W "Be it known that LHUGO J. BAoHMAN, a "citizen of the United States, residingat Denvenin the county of Denver and State of Colorado; 1 we invented certain new and useful Improvements in Pistons r of which the folio ing is a specification.

,Thisinvention relates to improvementsin reciprocating pistons of the type commonly used in the cylinders of pumps compressors, motors and othersiniilar machines, and more particularly to pistons for gas engines.

4' engines, the cylinder of which has morablehead, tho ron'ioval of the pisfroin; theoylindor is a ditlicultniatter, since it requires the removal of the crank case d other parts, causing great inconvenience. I t r Some. of the objects of this invention, there/fora so oonstrr and freely attached to the connecting rod, as to permit bodily removal of he pistonwithou; disturbing the conneetin rod i o I oer object to provide a construca which permits of the part ottho piston ntacts wiihtlie. cylinder wall, to be "moved for refinisning its surface,

or the machine nfithwhicli the piston tively connected I objects Willappeiir from the dosori'ption taken in connection with the i panying drawing, in which:

1 is an axial section through a pori a gas engine, and a piston made in once with this invention, showing the action of the piston with the connecting led of said gas engine.

i an end View of the piston shown 9 with the ineans for locking the Q'W'hich the parts of the piston are ed together, in its locked condition, i 1 3 fragmentary sectional view taken i ii a: i a v aiongthe linen--23 lug. 1, showing the rin -means above referred to, in the corn n in which the fastening device is una ens the piston parts, and 7 4 fi section tahen along the line 4ii,

ST. LOUIS, MISSOURI.

Specification of Letters lacent.

. ing rod. and nithout .case and crank.

are to provide a piston which is.

ngrings, or other repairs, I inou t tll0 118 C8SS1ty Qi; disturbing other led to permit of its adjustment for the re of gas and other engines lire can be removed through the head ends of the cylinders. In accordance with this in- Patcntod Nov. 25 1919. Applioation filed Hovembor 15, 1916. Serial 1T0; 131,518. w 4 I vontion, therefore, the piston comprises a' piston slicll and a carrior,-in the form of a sleeve, to which the Connor-ling rod is 'attached. Thecarrier is arranged to seat within the piston shell, but the shell is freely removable ondwise from the carrier. A de tacliable connection, accessible 'i'roni thehoad end of the cylinder, is provided between the shell and carrier; whereby the piston shell can be. readily detached from and removed through the head end otthe'cylinder, \VlillOUij disturbing tliecoiniection bn- I tween the carrier and its attached connectlte'ferring more specifically to the draw" dismantling-the crank ings, Fig. 1 shows a trunk piston, comprising, an innerlbody part or carrier Qto which the pistonor connecting-rod is attachochan d an outer piston shell or inanllo 3 which. is slidably fitted upon the carrier in coaxial relation thereto, so that the carrierseats froelynithin tho shell. m1

Both parts of the piston are cylindrical and closed at one of vtheir cnds,lho innerpart orcarrierbeinp; shorter than the outer pot or shell and fitted in the closed end thereof; the cooperatingfaces of the shell and carrier are machined so as to position the shell freely but accurately over the carrier. The shell 3 or the piston has on its end-Wall a central, inwardly projecting tenon l of angular section which is fitted in a correspondingly formed socket 5 in the outer surface of the end-mill ofthe carrier,

to prevent rotation of either part with relation to the other when thcy are connect-ed;

The "arrier 2 of the piston has at its open end, two diametrically opposite, inwardly projecting bosses 6 which have axially alined bores to receive the ends, of a pin 7' by which the head of a connecting rod of'fitted bctweentlie bosses, is pivotallysccured, and a set-screw Q extendnig through a threaded aperture in one of the bosses engages the pin to hold it against rotatioiif The shell 3 of the pistonhasin its exterior v surface a number of circumferential grooves 1n wlnch packing r1ngs 1 0 are fitted for the ment by a square-head bolt 12 which extends through registering threaded openings in both of the end walls of the two parts. To look this bolt against accidental displacement, a washer 13 is provided, having four wings, which in their normal condition as shown in Fig. 3, abut against a corresponding number of lugs ll formed integrally With the end wall of the outer shell 3, atqu'adrant points around its bolt-hole. The washer is made of pliable material, and by bending one of its wings outwardly against a face of the bolthead, as shown in Figs. 1 and 2, the bolt is securely locked against rotation.

lVhen the carrier and piston shell are secured together, as shown in Fig. 1, they will form in effect, an integral trunk piston structure, as they are secured both laterally and axially with the required accuracy, but

so freely as to permit bodily removal of the piston shell from its carrier.

The cylinder in which the piston is used may be of a type common in engines, pumps, compressors, motors and similar machines. and, as herein shown sulliciently for purposes of illustrating this invention, comprises a cylinder (l of a gas engine E that has a cover or head ll detachably secured to its upper or head end. The head H is readily removable from the cylinder (7 to permit access to parts within the cylinder. such as the means which secures the piston shell to its carrier, so that the said shell may be de tached from its carrier and withdrawn from the open head end of the cylinder.

lVhen it is desired to remove the piston from the cylinder. for refinishing .its surface, replacing one or more of the packing rings, or other repairs. the cylinder head H is removed, and by then loosening the screw 12, the piston shell 3 can be bodily or as a unit removed from its carrier without dis tin-hing the connecting rod. It will be understood that the bent wing of the washer 13 is returned to its original position by bending it against the surface of the piston, and the bolt l2 being thus released. is turned until its inner end is free trom'the carrier of the piston, but still engages the thread in the, piston shell. The bolt when in this position provides a ready means for engage ment by a tool to effect the removal of the piston-mantle or shell by sliding it longitudinally through the open end of the cylinder. The presence of the piston rings on the piston, of course, necessitates the provision ol means whereby a part, such as 12, on the piston can be, gripped by any suitable tool as the piston is normally flush with the end of the cylinder.

It will be observed that since the piston is a trunk piston, having its head end (that is the end exposed to the gases) closed, and

the walls of the cylinder can, therefore, be so readily observed.

When the piston shell is again replaced, the provision of the beveled edge of the shell. causes this shell to center itself on the carrier and, therefore, permits quick and accurate replacementof the piston shell on its carrier. After the shell is replaced the screw 12 is tightened and locked by turning up one of. the wings on the Washer 13 as shown in Figs. 1 and 2.

It is understood that the construction and relative arrangement of the parts of which the in'lproved piston is composed, may be varied within the spirit of the invention in" accordance with the design of the engine or the machine of which the piston is a par]; It is further obvious that various chang g may be made. in the details of construct without departing-from 'the spirit of this iiivention. .lt therefore, to be underst d that this invention is not to be limited to-th specific construction shown and described.

Having thus described the invention, what is claimed is:

l. A. piston composed of two cylindrical 1 parts closed at one end and fitted one around the other for longitudinal removal, the said chased ends oi the parts having register ing threaded openings for the application of a bolt to fasten them together, and the closed end of the outer part having lugs adjacent its'said openings, a headed bolt fitted in said openings, and a pliable washe having wings abutting against said lug s'a nd adapted to be bent in engagement with the head of the bolt for locking the same against rotation.

2. A piston composed of two cylindrical shells closed by heads at one of their ends and slidingly fitted one within the other 2 with their said heads adjoining one another, the inner shell having means for its connection with a motion transmitting agent, one of said heads having a non-circular socket and the other one having a. corre- 135 spondingly formed tcnon within the,socket, and means for uniting the two shells.

3. A piston composed of two cylindrical shells closed by heads at one of their ends and slidingly fitted one within the other 130 with their said heads adjoining one 'another, the inner shell having means for its connection with a motion transmitting agent, one of said heads having a non-circular socket and the other one having a correspondingly formed tenon Within the socket, said tenon and the bottom of said socket having alined apertures, and a bolt in said apertures to secure the shells together.

4. A piston comprising an inner, pitinanconnected member having an end wall and an outer member having an end wall, and fitting the inner member, the end walls of the two members being adjacent, means removably connecting said end walls consisting of a single screw, means to lock the screw from turning, and means to lock the two members against independent, turning movement.

A piston comprising an outer member and an inner pitman-connected member having adjoining end-walls and slidingly fitted one upon the other, said heads having cooperative means for holding the members against independent rotation, and a screw connecting the heads and adjustable from outside the piston, for disconnecting the same.

6. In a gas engine having a cylinder, a carrier adapted for attachment to a con necting rod, a trunk piston closed at its head and adapted to seat freely over said carrier, and constructed and arranged to permit its bodily removal and replacement from and on said carrier through the head end of the cylinder, and means operable from the head end of said piston adapted to detachably connect said piston with said carrier.

7. In a gas engine having a cylinder, a

-carrier having a wrist pin connection, a

trunk piston closed at its head end adapted to telescopically seat freely over said carrier, and constructed and arranged to permit its bodily removal and replacement from and on said carrier through the head end of the cylinder, and means operable from the head end of said piston adapted to detachably connect said piston with said carrier.

8. In a gas engine having a cylinder, a carrier sleeve of smaller diameter than the cylinder and having a wrist pin connection, a piston shell adapted to telescopically seat freely over said sleeve and form therewith a trunk piston, said piston shell bein constructed and arranged to permit its fiodily removal and replacement from and on said sleeve through the head end of the cylinder, and means operable from the head end of the piston adapted to detachably connect said shell to said sleeve.

9. The combination of a cylinder having a removable head, and a piston comprising two men'lbers, an inner one with which the pitman is connected, and an outer one titting over and removable from the inner one and from the cylinder by an outward endwise movement from the side opposite the pitman.

10. The con'ibination with a eylinderhaving a removable head, a piston comprising two lllBll'llJOl'S, an inner one and an outer one fitting over a wrist pin mounted within the inner piston member, and a pitnian connected with said wrist pin, said outer piston member being removable from the inner member and from the cylinder by an out ward endwise movement from the side opposite the pitman.

In testimony whereof I have atiixed my signature in presence of two witnesses.

HUGO J. BACHBIAN.

Witnesses G. J. ROLLANDET, L. Rumors. 

